In-line configured printers are important because they minimize the length (along the substrate or printing medium) of the print zone, and thereby minimize the overall envelope of the printing machine. Accommodating a longer print zone expands the overall printing machine envelope which is critical to cost, weight, installation space, inventory and shipping. In-line printers, particularly in-line printers for printing indicia, return address, destination address and/or destination barcode together with optional message line and/or destination barcode on a substrate such as a mail piece, use multiple spaced assemblies of print heads to carry out the required printing.
The positioning of the print head assemblies in such in-line printers is typically accomplished by manual movement of the assemblies with respect to one another in those in-line printers that have movable print head assemblies and after such manual location are then locked in a fixed location. The position of the various areas of information to be printed are located relative to one another with variable spacing depending upon the width of the printing medium material, such as, for example, a print stock postal card, an envelope such as a #10 business envelope, a 9".times.12" flat mailing envelope or custom-sized envelope, to be printed. In such in-line printers, a first multiple print head assembly is located to print in a fixed print area of the substrate as the substrate passes relative to the print head. The first multiple print head assembly may be aligned and located to print in a fixed print area that, for example, may be in the print area that includes the return address or other indicia information. A second multiple print head assembly is located relative to the first print head assembly and positioned to print in a second print area, which may include, for example, the destination address and/or destination barcode. A third multiple print head assembly is located and positioned relative to the second and first multiple print head assemblies and located to print in a third print area, which may include, for example, a message line or optional barcode. The location of the first, second and third print areas on a mail piece are within predetermined areas of the mail piece and are typically specified by United States Postal Service standards to accommodate mechanized mail processing for each of the differently sized mail pieces. When a user desires to print with an in-line printer on a differently sized substrate or mail piece, the print head assemblies must be repositioned and located and locked in a different position to meet the location print area requirements for the size of the mail piece being printed.
In-line printers such as those described above require operator intervention to relocate and reposition the multiple print heads each and every time a differently sized mail piece is printed. The operation and set-up of such in-line printers is labor intensive and cumbersome and less than satisfactory. In addition, the continual resetting and repositioning of the print head assemblies relative to one another may lead to positional error and requires constant verification that the print head assemblies are positioned and located properly to meet the addressing standards for the given size mail piece.
Accordingly, it would be desirable to provide an in-line printer having multiple print head assemblies that are individually controllable and automatically positionable and movable relative to one another to accommodate different width substrates to print on each of the desired print areas as the substrate and print head assemblies move relative to one another to print in each of the predetermined print areas of a mail piece.
It is an additional object of the present invention to provide an in-line printer that automatically determines the dimension of the mail piece as it is fed into the printer for controlling the print position of the assembly of print heads.